compound property: property that comprises other (possibly nested) scalar or compound properties, and has as many values as it has (nested) properties.
Note: A compound property is a generalization of a structured, multi-component property such as a vector, matrix, higher order tensor or computer data record.
Examples: 3D Cartesian coordinate, velocity vector, complex number, quaternion, rotation matrix, elasticity tensor, time-stamped diagnostic message.
physical dimension: synonym of quantity dimension
precision: maximum number p of significant digits that can be represented in a format, or the number of digits to that a result is rounded.
Source: IEEE-Std-754-2008.
Note: In this definition the kind of 'digit' depends on the selected format: in a 'binary format' is it a 'binary digit', in a 'decimal format' it is a 'decimal digit'.
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quantity: property of a phenomenon, body, or substance, where the property has a magnitude that can be expressed as a number and a reference
Source:
VIM
quantity dimension: expression of the dependence of a
quantity on the base quantities of a system of quantities as a product of powers of factors corresponding to the base quantities, omitting any numerical factor
Source:
VIM
scalar property: property with a single value
system: combination of interacting elements organized to achieve one or more stated purposes
Note 1: A system may be considered as a product or as the services it provides.
Note 2: In practice, the interpretation of its meaning is frequently clarified by the use of an associative noun, e.g., aircraft system. Alternatively, the word “system” may be substituted simply by a context-dependent synonym, e.g., aircraft, though this may then obscure a system principles perspective.
Source: ISO 15288:2008
system element: member of a set of elements that constitutes a system
Note: A system element is a discrete part of a system that can be implemented to fulfil specified requirements. A system element can be hardware, software, data, humans, processes (e.g., processes for providing service to users), procedures (e.g., operator instructions), facilities, materials, and naturally occurring entities (e.g., water, organisms, minerals), or any combination.
Source: ISO 15288:2008
system property: named observable characteristic of a
system or
system element
simplification of “any named, measurable or observable attribute, quality or characteristic of a system or system element”: “observable” includes “measurable”, “characteristic” includes “attribute” and “quality”
Source:
SEBoK, derived from
SE Conceptual Model Semantic Dictionary (Draft #12, 2003-03-27)
value: particular magnitude or designation for a given observable characteristic
Examples: (1) the value 1540.5 expressed in kilogram for the “mass” property of “my car”, (2) the value red for the “color” variable, (3) the default value true for the “isEncrypted” boolean formal parameter of operation “sendData”, (4) the value 299792458 expressed in m/s for the “speed of light in vacuum” physical constant.
value type: named definition of the essential semantics and structure of the set of possible values of an observable characteristic, without the value itself